How brain flexibility emerges in infants

Scientists say they’ve discovered that cognitive flexibility, a critical higher order brain function, starts developing during the first two years of life.

Having cognitive flexibility – the mental capacity to switch between different concepts – is associated with better reading ability, academic achievement, resilience and creativity, while less mental suppleness is linked to risk of neurological and psychiatric disorders.

Until now, it’s been difficult to assess higher order brain functions during infancy. But recent imaging evidence suggests such abilities emerge earlier than previously thought, according to Weili Lin from the University of North Carolina, US, senior author of a study published in the journal Proceedings of the National Academy of Sciences.

This prompted his group to explore cognitive flexibility during these early years.

“It has been widely documented that the ability of cognitive flexibility in pre-school age children predicts academic success and plays a pivotal role in our daily life,” he says.

“Therefore, we were interested in understanding the developmental processes of cognitive flexibility during the first two years of life, one of the most critical time periods of brain development.”

For the study, magnetic resonance images were collected from 52 normally developing infants as they were sleeping on seven occasions from birth to two years to measure neural flexibility, which is thought to underlie cognitive flexibility.

The children were followed up at five to six years of age, when the team administered the Differential Ability Scales, a battery of cognitive and achievement tests.  

Results showed that neural flexibility increased with age across most of the higher brain networks associated with attention, memory and response inhibition, showing the emergence of a “functionally flexible brain during the first two years of life”, says Lin.

Higher neural flexibility at just three months of age was associated with reasoning and conceptual abilities five to six years later.

Comparisons with teenage and adult data sets showed that the so-called “flexible club”, a group of highly flexible brain regions, were also those with the highest age-related increases in the two-year-olds’ neural flexibility.

Measuring neural flexibility during infancy could offer opportunities to explore how the development of these brain regions responds to learning and interactions with the environment, says Lin.

He suggests this approach might also help identify early neural underpinnings of developmental disorders.